1. Technical Field
The present disclosure relates to a refrigerating cycle apparatus.
2. Description of the Related Art
Halogenated hydrocarbons such as chlorofluorocarbon and alternatives for chlorofluorocarbon have been widely used as refrigerants for refrigerating cycle apparatuses. However, such refrigerants may lead to destruction of the ozone layer and to global warming. To solve the problem, a refrigerating cycle apparatus that uses water, which has very small impact on the global environment, as a refrigerant has been developed.
As illustrated in FIG. 10, Japanese Patent No. 4454456 discloses a closed system refrigerating apparatus 300 that uses water as a refrigerant. The refrigerating apparatus 300 includes an evaporator 316, a condenser 318, and a connection pipe 319, and a compressor 320. The condenser 318 is coupled to the evaporator 316 through a connection pipe 317. The connection pipe 319 connects the evaporator 316 to the condenser 318. The compressor 320 is disposed on the connection pipe 319. The evaporator 316 is a shell and tube evaporator, for example, which includes a cylindrical body with multiple cooling tubes inside it. Water refrigerant is separated into liquid and vapor in the cylindrical body, and the vapor is drawn into the compressor 320. The cooling tubes are immersed in the water refrigerant. Brine or water flows through the cooling tubes. Latent heat of vaporization of the water refrigerant cools the brine or water flowing through the cooling tubes.
As illustrated in FIG. 11, International Publication No. WO2012/147366 discloses an air conditioner 500 that uses a refrigerant including water, alcohol, or ether, for example, as a main component. The air conditioner 500 includes a refrigerant circuit 502, a first circuit 504, and a second circuit 505. The refrigerant circuit 502 includes an evaporator 525, a vapor channel 502a, a condenser 523, and a liquid channel 502b. A first compressor 521 and a second compressor 522 are disposed on the vapor channel 502a. Ends of the first circuit 504 are connected to the evaporator 525, and ends of the second circuit 505 are connected to the condenser 523. The first circuit 504 circulates the liquid refrigerant stored in the evaporator 525 through an indoor heat exchanger 531 (first heat exchanger). The second circuit 505 circulates a liquid refrigerant stored in the condenser 523 through an outdoor heat exchanger 533 (second heat exchanger).
A first pump 540 is disposed upstream of the indoor heat exchanger 531 on the first circuit 504. A second pump 550 is disposed upstream of the outdoor heat exchanger 533 on the second circuit 505. A section between the first pump 540 and the indoor heat exchanger 531 in the first circuit 504 intersects a section between the second pump 550 and the outdoor heat exchanger 533 in the second circuit 505, and a first four-way valve 561 is disposed at the intersection. Furthermore, a section between the indoor heat exchanger 531 and the evaporator 525 in the first circuit 504 intersects a section between the outdoor heat exchanger 533 and the condenser 523 in the second circuit 505, and a second four-way valve 562 is disposed at the intersection. The air conditioner 500 is operated in either of a cooling mode and a heating mode by shifting the first four-way valve 561 and the second four-way valve 562.